Tephrocactus muellerianus Backeb., Descr. Cact. Nov. 1: 8. 1957 ["1956"] Tephrocactus muellerianus Backeb., Descr. Cact. Nov. 1: 8. 1957 ["1956"]is basionym for Opuntia muelleriana (Backeb.) G.D.Rowley in Natl. Cact. Succ. J. 13: 6. 1958Taxon for this nameTephrocactus muellerianus Backeb.